Learn Dutch: Ik vraag me af in hoeverre deze provider betrouwbaar is. - I wonder to what extent this provider is reliable.

The phrase in hoeverre introduces an indirect question, which acts as a subclause. Because of this, it forces the conjugated verb is to the very end of the sentence.

Why do we say "vraag me af" instead of just "vraag"?

The verb used here is zich afvragen, which is a separable reflexive verb meaning "to wonder". Because it is the main clause, the separable prefix af moves to the end of that clause (right before the subclause begins), and the reflexive pronoun me matches the subject ik.

How can I tell that the English loanword "provider" takes "deze" instead of "dit"?

English loanwords for people, agents, or services (like provider, manager, or computer) are almost always de-words in Dutch. Therefore, you use deze (this) instead of the het-word equivalent dit.

Can I use "hoeveel" instead of "in hoeverre" here?

Not quite. While both relate to amounts, hoeveel means "how much" or "how many" in a measurable, quantitative sense. The phrase in hoeverre means "to what extent" or "to what degree", which is the correct choice when asking about a quality like being betrouwbaar (reliable).